Flash lamp



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June 20, 1939. I c. KORVER FLASH LAMP original Filed April 26, 1955 als Patented June 20, 1939 Y FLASH LAMP Cornelis Korver, Eindhoven, Netherlands, assignor to N.

V. Philips Gloeilampenfabrieken.

Eindhoven, Netherlands Original application April 26, 1935, Serial No.

Divided and this application July 16,

1936, Serial No. 91,003. In Germany May 18, 1934 3 Claims.

My present invention relates to hollow bodies and more particularly to ashlight lamps having a filling of wire of little absolute strength, and this application forms a division of my pending application Serial No. 18,457 filed April 26th, 1935, now Patent No. 2,115,423.

, rAccording vto the-invention the filling of wire of little absolutestrength is substantially evenly distributed. throughout the volume of the body.

It is very diilicult, if not impossible, to transport or carry such a wire for obtaining the lling according to the invention and due to this circumstance articles according to" my invention have not been manufactured before.

In accordance with the present invention the transportation of a Wire of small absolute strength into a limited space is effected by means of a gas which medium carries the wire along with it.

As is described in my above-mentioned patent, the wire so carried can be distributed with great uniformity and in a curled state within the limited space.

By wires as used herein is meant not only metal wires, but also glass wires, artificial silk Wires and the like.

In addition to transporting the wire, the gas used as carrying means also has a straightening action upon the wire, so that the curling power of the wire will cause no diiculties during the travel, such as the wire touching the inner surface of the tub-e through which it is being transported.

Particularly good results are obtained when the wire together with the incoherent medium is led through a tube which opens into the limited space and in which the tube openings for the inlet of the wire and of the gas are so located and dimensioned with respect to its outlet opening into the limited space, that the rate of ow of the medium is reduced upon entering this limited space.

As a rule, such thin wires inherently have sufcient internal strain to assume the desired curling upon entering the space,-and to permanently retain such curling. In case the wire has insuiiicient internal strains to assume such curling the required internal strains may be imparted thereto before it is carried into the limited space, for instance by drawing the wire over an angular body.

As has been stated above, the invention is particularly well adapted for placing a fine lling within flash lamps, Flash lamps manufactured in accordance with the invention have the important advantage that the combustion is so complete that a maximum yield of actinic light is insured. Due to such complete combustion the objectionable phenomenon of molten unburned metal particles being thrown against the wall of the bulb and causing bursting of the bulb, which frequently occurs in the case of incomplete combustion, is also avoided.

To obtain complete combustion in prior art lamps, a large excess of oxygen was used; i. e. much more than theoretically required; in flash lamps manufactured according to the invention the provision of much excess oxygen is unnecessary, and therefore a comparatively low-pressure gaslling can be used. This has the further advantage that the danger of the bulb bursting during the combustion is also eliminated.

The ash lamps manufactured in accordance with the invention have a very short flash-time, for instance V40 sec. or even less, and also a very short contact time, for instance 3&5 Sec.; in addition the flash lamps made in accordance with the invention can be manufactured in ma'ss production with highly uniform dash-time and contact time.

The term contact time" is to be understood to mean the lapse of time between the instant at which current is supplied to the bulb and the instant at which the emission of actinic light begins.

In order that the invention may be clearly understood and readily carried into effect, it will be described more fully with reference to the accompanying drawing, in which,

Figure l is a partly sectionized side view of a device suitable for carrying out the invention, and showing a flash lamp bulb lled with fine wire;

Fig. 2 is a sectionized view of Figure 1 taken on the line I-I of Fig. 1;

Fig. 3 is a view of a finished ash lamp having a Wire lling placed therein.

Referring to Figs. 1 and 2,' a ash lamp bulb I having a glass envelope comprising a neck portion Il, is arranged with its neck portion extending over a portion of a guide tube 4. The bulb is shown in the process of being lled with a thin wire 2, having an absolute tensile'strength of about 25 grams; the wire passing through the guide tube 4. The guide tube 4 is formed on its end removed from the bulb, with a small funnelshaped aperture 3 and on its other end with ra portion 6 of enlarged diameter, and is also provided with an extension 50 through which enters the incoherent medium, for instance compressed air.

The compressed air flows in a direction indicated by the arrows I2 from a source of supply (not shown) through an inlet 5' to a control valve V (see Fig. 2), later to be more fully described, through the valve V and tubes 5 and 59 into the guide tube 4.

In starting the operation of placing the wire into the bulb, a short end-portion of the wire 2 is first treated to remove any internal strains and consequently to eliminate any tendency oi' this portion to coil; this being done, for example. by heating the wire, for instance in the case of magnesium wire, by annealing the portion of the wire at a temperature of 'from 300 to 400 C. for about five seconds. The wire portion so treated is then led through the aperture 3 to extend a short distance into-the guide tube 4 so that, upon admittance of the incoherent medium, the wire 2 will be transported along the tube and into the bulb I.

The construction of aperture 3 causes substantially the entire compressed air stream to flow towards the bulb I and then to pass to the outside along the space formed between the tube 4 and the neck portion II, as is indicated by the arrow. The compressed air ows through the tube 4 with considerable velocity and causes the wire 2 to be carried into the bulb, and at the same time tends to straightenthe wire while in the tube 4, so that the feeding of thewire into the bulb will take place in a continuous, uninterrupted operation without the formation of wire pellets within the tube 4, caused by friction due to the wire coming into contact with the tube wall.

Due to the tube being enlarged at 6, the velocity of the compressed air in tube portion 6 is greatly reduced, which causes the wire 2 to resume itsnatural curling and to uniformly flll up the bulb I.

The supply of wire 2 and the control of the flow of the compressed air to tube 4 takes place by means of a device A; the parts of which are mounted on a common base plate 2l. The device A comprises a bearing block I9, secured to the base plate 2l by means of four screws I9' and supporting a shaft I3, which shaft is xedly secured to block I9 by a set screw 20. Rotatably mounted upon the shaft I3 is a pulley I4 having two V-shaped grooves 10-1I; groove 10' serving to drive the pulley by means of a belt from a driving source (not shown), for example from an electric motor, and the groove 1I serving for a purpose later to be described.

The pulley I4 is provided on one side with a boss 65, acting as a bearing against the block I9, and on its other side with a counterbore 90 containing a thrust bearing I6. Secured to one side of the pulley is a friction ring I 8, for a purpose later to be described. The pulley I4 is continuously rotated during the operation of the device.

Rotatably and slidably mounted on the shaft I3 is a bushing 8 having fixedly secured at one end, by means of a pin 66, a flanged disc 9. Arranged on the bushing 8 so as to move therewith-,- and with the flange 9-is a spool 1 upon which is wound a supply of the wire 2.

Secured-to the base plate 2| by screws 61 is an angle bracket 68 having secured to its upstanding leg, a pad I of friction material. In the position shown the disc 9 is forced against the pad I0 by a compression spring I1 acting through the thrust bearing I6 upon the pulley I4, thus causing the disc 9, bushing 2, and reel 1 to remain at rest.

Arranged with a free fit over bushing 8 and bearing with one side through a thrust btling Il upon the side of spool 1, is one end 22' of an arm 22 whose other end is fixedly secured by means of a pin 13 to a rod 23 carrying at one end a push button 24.

The rod 23 is suitably guided so as to have axial movement-as indicated by the double-headed arrowby two projections 50-5I of a supporting bracket 3l, which bracket is secured to the base plate 2I by means of screws 60. 'I'he pro- .jection I also serves as the valve V, which controls the flow of compressed air to the tube 4, and for this purpose Is provided with passageways 26 and 26 through which may iiow the compressed air. I

'I'he rod 23 is provided with a portion 25 of reduced diameter, which, when the rod is in the positiongshown by the dotted lines, connects the passageways 26 and 26', and thus permits the flow of air. In the position shown the rod 23 intercepts the passageways 26-26, and thus prevents the flow of air.

Uponmovement of the push button 24-and rod 23in the direction indicated by the arrow 15, the end 22' of arm 22, acting through thrust bearing I5, moves the reel 1-`together with the bushing 3 and disc 9--against the compression of spring I1. If the pushbutton is moved into the position indicated by the dotted lines, flange 9 will assume the position shown in dotted lines with its surface in contact with the friction ring I3.` Thus flange 9-together with the bushing 8 and reel 'I-will be driven by and rotate with the pulley I4. 'I'hls movement of the push button 24-and the rod 23also brings the reduced portion 25 into alignment with the passageways 26 and 26' and interconnects same to permit the flow of compressed air to the tube 4. The reduced portion 25 is so located on the rod 23 that the interconnection of passageways 26 and 26', and thus the ow of air, takes place before the flange 9 contacts with the friction ring I8; i. e., before the reel 1 rotates and the supplying of the wire 2 begins.

Secured to the base plate 2I by screws 9i is a supporting block 30 having rotatably mounted thereon a shaft 29. Fixedly secured to the shaft 29 by a pin 92 is a grooved pulley 21, which pulley, together with the shaft 29, is driven bya belt 55-indicated in dot-dash line-from the groove 1I of pulley I4. Secured to a reduced portion 56 of shaft 29 by means of a nut 33 is a drum 29 having a surface 28', over which is drawn the wire 2.

The Wire 26 is so `driven from the pulley I4 that the peripheral speed of the surface 28' is greater-for instance 10% to 15% greater-than the greatest speed at which the wire leaves the reel 1. Due to this increased speed there is a certain amount of sliding friction between the wire 2 and the surface 28', which keeps the wire portion between the drimi 28 and reel 1 under tension, and thus insures that the unwinding of the wire from the reel 1 proceeds at the desired speed.

If the wire 2 does not inherently possess suilcient internal strain to receive the desired curlling upon entering the bulb, the desired internal strain may be imparted to the wire, and for this purpose a device C is provided.

The device C consists of a rod 34 having a diametrical and axially-extending slot 32 (see Fig. 1) through which passes the wire 2; the rod 34 being supported by a bracket 63 secured to the base plate 2l.- The rod 34 is supported so asto be adjustable about its axis and adapted to be secured in the desired position by means of a set screw it. Thus the rod Il can be secured in the desired position with the slot I2 at the correct angles to give the wire the desired amount 5 of curling power.

With the push button 2l pushed in. both the wire and the compressed air is being supplied to gli: tube l and the bulb becomes lled with the e. A After the bulb i has'been lled with the desired length fwlre, the push button 24 is released and the disc 9 is disconnected from the friction disc I8 by the spring l1 and is immediately Placed into contact with the friction pad I0, which stops vus the movement of the reel 1 and the supplying of wire to the tube 4. Such releasing of the push button also causes the rod 23 to interrupt communication between the passageways 2t and 2t', and thus interrupts the supply of compressed air. Due to the disposition of the portion 2B on the rod 23, the supply of air continues until after the reel 1 has come to rest. Subsequently the bulb I is moved to the right and the wire is severed by means of a suitable cutter, indicated by t8. a Various factors influence the operation, for instance, the peripheral speed of the reel 1: the internal diameter and length of tube 4; the speed of the compressed air through the tube; the diameter and length ot the end portion t; as! weli ao as the sizes of the bulb and of the neck portion Il. I'hese factors have to be selected with regard to the specific properties of the particular wire used in order that there be no bunching or bundling of the wire while filling; i. e. that the density of the filling be substantially equal throughout the bulb. and in addition, that the wire filling elastically bears against the bulb wall and be immovable within the bulb.

For .examplepin the case of a specidc flash l o lamp having a content of about 100 c. c. and an external diameter of about mm., 10 meters of wire having a diameter of 35 microns and consisting of an aluminium-magnesium alloy containing 8% magnesium, are used. In such lamp u dimensions and factors the following were found satisfactory: The neck portion il having a length of about 50 mm. and-anexternal diameter o! about 30 mm.: the guide tube C having a total length of mm. and the portion t a length of 40 mm.: the opening ofthe aperture 3 having a diameter of about 0.12 mm.: the diameter oi' the tube about 1.9 mm.: and the widened portion l a diameter of about 13 mm. Under these conditions, when using comprsed air at an overu pressure of two atmospheres, the wire moved at the rate o! about l meter per second.

Aflashlampniledinthismannerisillustrated 'in Pig.- 3 and comprises a bulb 3l containing a wire filling 3l oi' the above-mentioned material. 'I'he flash lamp is provided with the two terminal wires "-31 connected with one end to' the terminals of base 4I and carrying at their 5 other ends a filament 3l provided with an ignition mixture 3l consisting, for example, of a pulverized metal, for instance aluminium, an oxidizing agent, for instance lead dioxide, and a binder, for instance nitro-cellulose or siliceous varnish. The bulb 35 contains a gas iilling o! oxygen at a pressure of V3 atmosphere.

The term undulated wire as used in the claims is to be understood tomean a wire which per se is provided with undulations e. g. kinks or' waves. The term serpentine course is to be understood to mean a course which is winding or turning vone way and the other like that of a moving serpent.

While I have described my invention in connection withspeciilc examples, and in specic applications. I do not wish to be limited thereto, but desire the appended claims tobe construed as broadly as permissible in view of the prior art.

What I claim is:

l. A dash-lamp comprising a container of actinic light-transmitting material having an active portion, a mass of thin undulated wire disposed withinsaid active portion so as to be elastically ,o supported from the wall thereof. and a substance which upon ignition enters into an actinic reaction with said wire. said wire being in substantially uniform special distribution throughout said active portion with each unit length of the u wire surrounded by substantially the same amount of said substance.

2. A dash-lamp comprising a container of aetinic light-transmitting material having an active portion, a mass of thin undulated wire disa posedwithin said active portion so as to be elastically supported from the wall thereof, and a gas which upon ignition enters into an actinlo reaction with said wire, said wire being arranged inaserpentinecoursesoastobeinsubstan-a tialiy uniform spacial distribiion.

3. A flash-lamp comprising a container or aetinic iight-transmitting material having an aetive portion, a skeleton-like mass oi' thin wire provided with a large number of undulations. w

said mass being disposed within said active portion withthe tips of a large number of the outer undulations in contact with the wall of the container so as to eiasticaliy support the maas. and a gas which upon ignition enters into an ac u tinic reaction with said wire.

com KORVIB. 

